Turbomachines transfer energy between a rotor and a fluid, and include both turbines and compressors. A turbine transfers energy from a fluid to a rotor (impeller), while a compressor transfers energy from a rotor (impeller) to a fluid. In general, there are open and closed turbomachines. Open machines, such as propellers, windmills, and unshrouded fans act as an infinite extent of fluid, while closed machines operate on a finite quantity of fluid as it passes through a housing or casing. Turbomachines are also categorized according to whether they are axial flow machines or radial (centrifugal) flow machines.
Compressor turbomachines and turbine turbomachines typically include a rotating shaft located in a body or housing with an impeller at one end. Rotation of the shaft causes rotation of the impeller which in turn compresses or facilitates the flow of the fluid. Bearings, such as roller bearings, are provided to allow the shaft to rotate freely.
Correct lubrication is important to the performance and life of the bearings. For bearings which are permanently lubricated, it is also necessary to equalize pressure differentials that could force the lubricant from the bearings. Retainer members can be utilized to assist in preventing loss of lubricants from the bearings, as well as to prevent contaminants from entering the bearings, and decreasing their performance and durability.
With high speed turbomachines, it is also significant to prevent the outer races of the roller bearings or the bearing retainers from rotating at the same speed as the shaft and impeller, thereby increasing their duration and performance.
It thus is an object of the present invention to provide an improved retention member for a permanently lubricated bearing, and an assembly of a permanently lubricated bearing and an improved retention member, wherein retention of the lubrication is improved, as well as the durability and life of the assembly is improved. It is another object of the invention to provide an improved roller bearing and retainer assembly, as well as an improved retainer member for a roller bearing.